Gonadorelin, also known as gonadotropin-releasing hormone, gonadorelin acetate and GnRH, is a peptide made up of 10 amino acids. Gonadorelin peptide acts on the pituitary gland and is responsible for stimulating the release of several hormones, such as follicle stimulating hormone and luteinising hormone . The frequency and concentration of gonadorelin pulses, as well as the feedback of other hormones, such as androgens and oestrogens, control the stimulation of these hormones. Gonadorelin also stimulates natural testosterone release, which has a number of benefits related to bodybuilding . Testosterone is a potent anabolic hormone and has been shown to promote IGF-1 secretion and enhance the effect of growth hormones inside the body . Combined administration of testosterone and growth hormone has also been shown to cause substantial gains in lean mass, muscle strength, and aerobic endurance along with reductions in total body fat and trunk fat . Gonadorelin has been tested in human subjects and is used to treat a range of fertility-related diseases due to its abilities in modulating sex-hormone production. Administration of GnRH in physiologic concentrations and frequency stimulates the ovaries and induces ovulation in conditions such as polycystic ovarian disease . There are also treatment schedules in which gonadorelin agonists are used to aid in assisted reproduction. In these cases, gonadorelin is commonly used for ovarian hyperstimulation during in vitro fertilisation .
Gonadorelin has a distribution half-life of 2 to 10 minutes and a very short terminal half-life of 10 to 40 minutes . It is broken down by hydrolysis into smaller peptide components and is released by normal excretion from the body. Therefore, 100 mcg of gonadorelin can be administered daily by subcutaneous injection to mimic the body’s natural testosterone cycle.
Gonadorelin is approved for clinical usage in humans and is considered safe. Some reported side effects of using the drug include headaches, flushing and nausea. No dangerous side effects have been reported at the recommended dosage.
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